/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the  "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
 * $Id$
 */
package wx.xml.xalan.xalan.templates;

import javax.xml.transform.TransformerException;

import wx.xml.xalan.xalan.res.XSLTErrorResources;
import wx.xml.xalan.xalan.transformer.TransformerImpl;

/**
 * Implement xsl:comment.
 * <pre>
 * <!ELEMENT xsl:comment %char-template;>
 * <!ATTLIST xsl:comment %space-att;>
 * </pre>
 *
 * @xsl.usage advanced
 * @see <a href="http://www.w3.org/TR/xslt#section-Creating-Comments">section-Creating-Comments in XSLT Specification</a>
 */
public class ElemComment extends ElemTemplateElement {
    static final long serialVersionUID = -8813199122875770142L;

    /**
     * Get an int constant identifying the type of element.
     *
     * @return The token ID for this element
     * @see wx.xml.xalan.xalan.templates.Constants
     */
    public int getXSLToken() {
        return Constants.ELEMNAME_COMMENT;
    }

    /**
     * Return the node name.
     *
     * @return This element's name
     */
    public String getNodeName() {
        return Constants.ELEMNAME_COMMENT_STRING;
    }

    /**
     * Execute the xsl:comment transformation
     *
     * @param transformer non-null reference to the the current transform-time state.
     * @throws TransformerException
     */
    public void execute(
        TransformerImpl transformer)
        throws TransformerException {
        if (transformer.getDebug())
            transformer.getTraceManager().fireTraceEvent(this);
        try {
            // Note the content model is:
            // <!ENTITY % instructions "
            // %char-instructions;
            // | xsl:processing-instruction
            // | xsl:comment
            // | xsl:element
            // | xsl:attribute
            // ">
            String data = transformer.transformToString(this);

            transformer.getResultTreeHandler().comment(data);
        } catch (org.xml.sax.SAXException se) {
            throw new TransformerException(se);
        } finally {
            if (transformer.getDebug())
                transformer.getTraceManager().fireTraceEndEvent(this);
        }
    }

    /**
     * Add a child to the child list.
     *
     * @param newChild Child to add to this node's child list
     * @return Child that was just added to child list
     * @throws DOMException
     */
    public ElemTemplateElement appendChild(ElemTemplateElement newChild) {

        int type = ((ElemTemplateElement) newChild).getXSLToken();

        switch (type) {

            // char-instructions
            case Constants.ELEMNAME_TEXTLITERALRESULT:
            case Constants.ELEMNAME_APPLY_TEMPLATES:
            case Constants.ELEMNAME_APPLY_IMPORTS:
            case Constants.ELEMNAME_CALLTEMPLATE:
            case Constants.ELEMNAME_FOREACH:
            case Constants.ELEMNAME_VALUEOF:
            case Constants.ELEMNAME_COPY_OF:
            case Constants.ELEMNAME_NUMBER:
            case Constants.ELEMNAME_CHOOSE:
            case Constants.ELEMNAME_IF:
            case Constants.ELEMNAME_TEXT:
            case Constants.ELEMNAME_COPY:
            case Constants.ELEMNAME_VARIABLE:
            case Constants.ELEMNAME_MESSAGE:

                // instructions
                // case Constants.ELEMNAME_PI:
                // case Constants.ELEMNAME_COMMENT:
                // case Constants.ELEMNAME_ELEMENT:
                // case Constants.ELEMNAME_ATTRIBUTE:
                break;
            default:
                error(XSLTErrorResources.ER_CANNOT_ADD,
                    new Object[]{newChild.getNodeName(),
                        this.getNodeName()});  //"Can not add " +((ElemTemplateElement)newChild).m_elemName +

                //" to " + this.m_elemName);
        }

        return super.appendChild(newChild);
    }
}
